The present invention relates to a snap terminal which provides a ring-shaped electrical and mechanical connection with the component to which it is connected.
Electrical terminals must be connected to certain articles of manufacture to allow for the flow of electricity from one medium to a different medium. This is particularly true in instances where the conductive elements are embedded in a non-conductive material, such as glass or dielectric substrate. In, for instance, automotive glass panels having electrical wiring embedded therein for the purpose of defogging the window, electrical terminals must be attached to the glass panels to provide a point of connection for electrical current input and output.
Snap terminals are sometimes employed in this fashion. Snap terminals are generally two-piece terminals which are arranged in a mating configuration. Each of the terminals is electrically and mechanically connected to a component and the snap terminal components are then mated to form a releasable electrical and mechanical connection between the components. Snap terminals are commonly provided on 9-volt batteries.
Many snap terminals are formed with solder to be soldered onto a specific component. Such male snap terminals are generally formed in one of two ways: xe2x80x9cstakingxe2x80x9d or xe2x80x9ccrimpingxe2x80x9d. A snap terminal formed by xe2x80x9cstakingxe2x80x9d joins two pieces. The first piece is a hat-shaped base. The hat-shaped base features a sunken top wall having a hole in its center. The side wall of the base extends upwardly from the periphery of the top wall, then downwardly to a lower end thereof. An outwardly extending annular flange extends from the lower end of the side wall. The second piece which is used in producing xe2x80x9cstakexe2x80x9d snap terminals is formed of solder. It consists of a circular disc of solder having a diameter that is similar to that of the annular flange. The solder disc has a perpendicular stake which extends from the center of the disc through the hole in the top wall of the base. The two pieces are pressed together so that when heat is applied the solder melts and adheres to the component.
The second type of snap terminal is formed by xe2x80x9ccrimpingxe2x80x9d. A snap terminal formed by the xe2x80x9ccrimpingxe2x80x9d method also joins two pieces: a hat-shaped base and a circular solder disc. Like the base used in the xe2x80x9cstakingxe2x80x9d method, the base used in the xe2x80x9ccrimpingxe2x80x9d method has a circular top wall, a vertical wall extending downwardly therefrom, and an annular flange. The solder disc which is joined to the base, has however, a diameter that is larger than that of the annular flange. The solder disc is placed substantially concentric to the annular flange and the solder at the periphery o the disc is wrapped around the annular flange and crimped into place. The xe2x80x9ccrimpedxe2x80x9d snap terminal is connected to the component in the same manner as the xe2x80x9cstakedxe2x80x9d terminal.
A newer style of male snap terminal is described in U.S. Pat. No. 5,897,406 to Benes et al. (xe2x80x9cBenesxe2x80x9d). The male snap electrical terminal described therein does not have a solder disc base, but has solder on the interior side wall and interior top wall of the terminal. Although the terminal described in Benes does not have a disc base, in use, the heating of the terminal to melt the solder and join the terminal to the subject component causes the solder on the interior side wall and top wall of the terminal to melt and pool at the bottom of the terminal, resulting in a disc-shaped connection between the terminal and the component.
Each style of existing snap terminal provides a solid circular connection between the terminal and the component. This configuration can be troublesome when the terminal is connected to a component having dissimilar properties such as heat expansion coefficients. If, for instance, a terminal is mounted on glass, a change in temperature will cause the expansion or contraction of the terminal, but have essentially no impact on the expansion or contraction of the glass. The solid circular connection prevents the deformation of the base and puts strain on both the connection and the glass.
A male snap electrical terminal is described which includes a base having a top wall, a vertical wall, and an annular flange, and which has a ring of solder on the annular flange, which provides a ring-shaped electrical and mechanical connection with the component to which it is connected. The ring-shaped electrical and mechanical connection allows the terminal to flex when stressed, such as by thermal expansion. Furthermore, the snap electrical terminal of this invention may be manufactured in one of two ways, either of which includes only two mechanical steps.
It is therefore a principal object of the invention to provide a snap electrical terminal that provides a ring-shaped electrical and mechanical connection with the component to which it is connected.
Yet another object of the invention is to provide a snap electrical terminal requiring only two mechanical steps for its manufacture.
These and other objects will be apparent to those skilled in the art.